# Copyright 2012 Pedro Navarro Perez
# Copyright 2013 Cloudbase Solutions Srl
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

"""
Helper methods for operations related to the management of volumes,
and storage repositories

Official Microsoft iSCSI Initiator and iSCSI command line interface
documentation can be retrieved at:
http://www.microsoft.com/en-us/download/details.aspx?id=34750
"""

import time

from oslo.config import cfg

from nova.openstack.common.gettextutils import _
from nova import utils
from nova.virt.hyperv import basevolumeutils
from nova.virt.hyperv import vmutils

CONF = cfg.CONF


class VolumeUtils(basevolumeutils.BaseVolumeUtils):

    def __init__(self):
        super(VolumeUtils, self).__init__()

    def execute(self, *args, **kwargs):
        stdout_value, stderr_value = utils.execute(*args, **kwargs)
        if stdout_value.find('The operation completed successfully') == -1:
            raise vmutils.HyperVException(_('An error has occurred when '
                                            'calling the iscsi initiator: %s')
                                          % stdout_value)

    def login_storage_target(self, target_lun, target_iqn, target_portal):
        """Add target portal, list targets and logins to the target."""
        (target_address,
         target_port) = utils.parse_server_string(target_portal)

        #Adding target portal to iscsi initiator. Sending targets
        self.execute('iscsicli.exe', 'AddTargetPortal',
                     target_address, target_port,
                     '*', '*', '*', '*', '*', '*', '*', '*', '*', '*', '*',
                     '*', '*')
        #Listing targets
        self.execute('iscsicli.exe', 'ListTargets')
        #Sending login
        self.execute('iscsicli.exe', 'qlogintarget', target_iqn)
        #Waiting the disk to be mounted.
        #TODO(pnavarro): Check for the operation to end instead of
        #relying on a timeout
        time.sleep(CONF.hyperv.volume_attach_retry_interval)

    def logout_storage_target(self, target_iqn):
        """Logs out storage target through its session id."""

        sessions = self._conn_wmi.query("SELECT * FROM "
                                        "MSiSCSIInitiator_SessionClass "
                                        "WHERE TargetName='%s'" % target_iqn)
        for session in sessions:
            self.execute_log_out(session.SessionId)

    def execute_log_out(self, session_id):
        """Executes log out of the session described by its session ID."""
        self.execute('iscsicli.exe', 'logouttarget', session_id)
